1. Technical Field
The present disclosure relates to orthopedic surgery apparatus for stabilizing and fixing the bones and joints of the body. Particularly, the present disclosure relates to a manually operated apparatus for reducing a spinal rod into a bone screw in a controlled, measured, and efficient manner.
2. Description of Related Art
The spinal column is a complex system of bones and connective tissues that provides support for the human body and protection for the spinal cord and nerves. The human spine is comprised of thirty-three vertebrae at birth and twenty-four as a mature adult. Between each pair of vertebrae is an intervertebral disc, which maintains the space between adjacent vertebrae and acts as a cushion under compressive, bending, and rotational loads and motions.
There are various disorders, diseases, and types of injury that the spinal column may experience in a lifetime. The problems may include but are not limited to scoliosis, kyphosis, excessive lordosis, spondylolisthesis, slipped or ruptured disc, degenerative disc disease, vertebral body fracture, and tumors. Persons suffering from any of the above conditions typically experience extreme or debilitating pain and often times diminished nerve function.
One of the more common solutions to any of the above mentioned conditions involves a surgical procedure known as spinal fusion. A spinal fusion procedure involves fusing two or more vertebral bodies in order to stabilize or eliminate motion at the intervertebral disc or joint. To achieve this, natural or artificial bone, along with a spacing device, replaces either part, or all of the intervertebral disc to form a rigid column of bone, which is stabilized by mechanical hardware.
The mechanical hardware used to immobilize the spinal column typically involves a series of bone screws/anchors and metal rods or plates. When the spine surgery is performed posteriorly, it is common practice to place bone screws into the vertebral bodies and then connect a metal rod between adjacent vertebral bodies. When the spine surgery is performed anteriorly, it is common practice to attach a thin metal plate directly to the vertebral bodies and secure it to each vertebral level using one or more bone screws.
The process of properly inserting the spinal rod into the receiving slot of a bone screws and then securing that connecting rod in place can often require that the clinician use a number of instruments and expend a great deal of time and effort. When bone screws in several adjacent vertebrae are to be securely connected by a spinal rod, the repeated process of inserting the rod into the screw housing of the bone screws and then securing the rod in place for each respective bone screw can be difficult, tiresome, and time consuming. Further, the alignment of the rod as it connects to each of the sequential bone screws may require adjustment during the procedure and, therefore it is desirable that an apparatus and method be provided by which the rod can be reduced into the screw housing of each of the sequentially aligned bone screws and, as necessary, easily adjusted so as to facilitate the process for the clinician with minimal effort and loss of time. Therefore, a need exits for an efficient way to reduce the rod into the screw housing and lock the rod in place.